Gliese 440

Gliese 440 seen by the Hubble Space Telescope[1]
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Musca[2]
Right ascension 11h 45m 42.91694s[3]
Declination −64° 50′ 29.4620″[3]
Apparent magnitude (V) 11.50[4]
Characteristics
Spectral type DQ6[5]
U−B color index -0.59[4]
B−V color index +0.19[4]
Astrometry
Proper motion (μ) RA: 2661.640 mas/yr[3]
Dec.: -344.933 mas/yr[3]
Parallax (π)215.6753 ± 0.0181 mas[3]
Distance15.123 ± 0.001 ly
(4.6366 ± 0.0004 pc)
Details
Mass0.56 ± 0.08[6] M☉
Radius0.01 R☉
Luminosity0.0005[7] L☉
Surface gravity (log g)8.27 ± 0.05[7] cgs
Temperature8,500 ± 300[7] K
Age(as white dwarf)[7]
1.44 Gyr
Other designations
GJ 440[8], HIP 57367[9], BPM 7108, Ci 20 658[10], EGGR 82, L 145-141, LAWD 37, LHS 43[11], LP 145-141, LPM 396, LTT 4364, NLTT 28447[12], PLX 2716[13], PM 11429-6434, WD 1142-645, TYC 8981-4417-1[14][15], GSC 08981-04418, 2MASS J11454297-6450297
Database references
SIMBADdata
Gliese 440 is located in the constellation Musca.
Gliese 440 is located in the constellation Musca.
Gliese 440
Location of Gliese 440 in the constellation Musca

Gliese 440, also known as LP 145-141 or LAWD 37,[4] is an isolated white dwarf located 15.1 light-years (4.6 parsecs) from the Solar System in the constellation Musca.[16] According to a 2009 paper, it is the fourth closest known white dwarf to the Sun (after Sirius B, Procyon B, and van Maanen's star.)[17]

History of observations

Gliese 440 is known at least from 1917, when its proper motion was published by R. T. A. Innes and H. E. Wood in Volume 37 of Circular of the Union Observatory.[18] The corresponding designation is UO 37.[10] (Note: this designation is not unique for this star, that is all other stars, listed in the table in the Volume 37 of this Circular, also could be called by this name).

Space motion

Gliese 440 may be a member of the Wolf 219 moving group, which has seven possible members. These stars share a similar motion through space, which may indicate a common origin.[19] This group has an estimated space velocity of 160 km/s and is following a highly eccentric orbit through the Milky Way galaxy.[20]

Properties

White dwarfs are no longer generating energy at their cores through nuclear fusion, and instead are steadily radiating away their remaining heat. Gliese 440 has a DQ spectral classification, indicating that it is a rare type of white dwarf which displays evidence of atomic or molecular carbon in its spectrum.[21]

In 2019, Gliese 440 was observed passing in front of a more distant star. The bending of starlight by the gravitational field of Gliese 440 observed by the Hubble Space Telescope allowed its mass to be directly measured. The estimated mass of Gliese 440 is 0.56±0.08 M☉, which fits the expected range of a white dwarf with a carbon-oxygen core. This measurement marked the first direct gravitational mass determination of a single white dwarf.[6]

Gliese 440 has only 56% of the Sun's mass,[6] but it is the remnant of a massive main-sequence star that had an estimated 4.4 solar masses.[22] While it was on the main sequence, it probably was a spectral class B star (in the range B4–B9).[23] Most of the star's original mass was shed after it passed into the asymptotic giant branch stage, just prior to becoming a white dwarf.

Search for companions

A survey with the Hubble Space Telescope revealed no visible orbiting companions, at least down to the limit of detection.[24][5]

Its proximity, mass and temperature have led to it being considered a good candidate to look for Jupiter-like planets. Its relatively large mass and high temperature mean that the system is relatively short-lived and hence of more recent origin.[22]

Hipparcos-Gaia proper motion shows an anomaly that hints to the presence of an exoplanet that has a mass of either 0.44 or 0.60 MJ which is between Saturn and Jupiter.[25][26]

See also

References

  1. ^ "LAWD 37". esahubble.org. 2 February 2023. Retrieved 21 April 2023.
  2. ^ "Constellation boundaries". Centre de Données astronomiques de Strasbourg. Retrieved 2007-07-16.
  3. ^ a b c d Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
  4. ^ a b c d "LAWD 37". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2007-07-16.
  5. ^ a b Daniel J. Schroeder; et al. (February 2000). "A Search for Faint Companions to Nearby Stars Using the Wide Field Planetary Camera 2". The Astronomical Journal. 119 (2): 906–922. Bibcode:2000AJ....119..906S. doi:10.1086/301227.
  6. ^ a b c McGill, P.; Anderson, J.; Casertano, S.; Sahu, K.C. (March 2023), "First semi-empirical test of the white dwarf mass-radius relationship using a single white dwarf via astrometric microlensing", Monthly Notices of the Royal Astronomical Society, 520 (1): 259–280, doi:10.1093/mnras/stac3532, hdl:10023/26568, retrieved 2023-02-08
  7. ^ a b c d Table 2, P. Bergeron; S. K. Leggett; María Teresa Ruiz (April 2001). "Photometric and Spectroscopic Analysis of Cool White Dwarfs with Trigonometric Parallax Measurements". Astrophysical Journal Supplement Series. 133 (2): 413–449. arXiv:astro-ph/0011286. Bibcode:2001ApJS..133..413B. doi:10.1086/320356. S2CID 15511301.
  8. ^ Gliese, W.; Jahreiß, H. (1991). "Gl 440". Preliminary Version of the Third Catalogue of Nearby Stars.
  9. ^ Perryman; et al. (1997). "HIP 57367". The Hipparcos and Tycho Catalogues.
  10. ^ a b Porter, J. G.; Yowell, E. J.; Smith, E. S. (1930). "A catalogue of 1474 stars with proper motion exceeding four-tenths year". Publications of the Cincinnati Observatory. 20: 1–32. Bibcode:1930PCinO..20....1P. Page 16 (Ci 20 658).
  11. ^ Luyten, Willem Jacob (1979). "LHS 30". LHS Catalogue, 2nd Edition.
  12. ^ Luyten, Willem Jacob (1979). "NLTT 28447". NLTT Catalogue.
  13. ^ Van Altena W. F.; Lee J. T.; Hoffleit E. D. (1995). "GCTP 2716". The General Catalogue of Trigonometric Stellar Parallaxes (Fourth ed.).
  14. ^ Perryman; et al. (1997). "HIP 57367". The Hipparcos and Tycho Catalogues.
  15. ^ Hog; et al. (2000). "TYC 8981-4417-1". The Tycho-2 Catalogue.
  16. ^ Henry, Todd J.; Walkowicz, Lucianne M.; Barto, Todd C.; Golimowski, David A. (April 2002). "The Solar Neighborhood. VI. New Southern Nearby Stars Identified by Optical Spectroscopy". The Astronomical Journal. 123 (4): 2002–2009. arXiv:astro-ph/0112496. Bibcode:2002AJ....123.2002H. doi:10.1086/339315. S2CID 17735847.
  17. ^ Table 1, Sion Edward M (2009). "The white dwarfs within 20 parsecs of the sun: kinematics and statistics". The Astronomical Journal. 138 (6): 1681–1689. arXiv:0910.1288. Bibcode:2009AJ....138.1681S. doi:10.1088/0004-6256/138/6/1681. S2CID 119284418.
  18. ^ Innes & Wood (1917). Page 290 (see string 41).
  19. ^ Eggen, O. J.; Greenstein, J. L. (1965). "Spectra, colors, luminosities, and motions of the white dwarfs". Astrophysical Journal. 141: 83–108. Bibcode:1965ApJ...141...83E. doi:10.1086/148091. — see table 5.
  20. ^ Bell, R. A. (1962). "Observations of some southern white dwarfs". The Observatory. 82: 68–71. Bibcode:1962Obs....82...68B.
  21. ^ Kawaler, S.; Dahlstrom, M. (2000). "White Dwarf Stars". American Scientist. 88 (6): 498. Bibcode:2000AmSci..88..498K. doi:10.1511/2000.6.498. S2CID 227226657. Archived from the original on April 18, 2005. Retrieved 2007-07-19.
  22. ^ a b Burleigh, M. R.; Clarke, F. J.; Hodgkin, S. T. (April 2002). "Imaging planets around nearby white dwarfs". Monthly Notices of the Royal Astronomical Society. 331 (4): L41–L45. arXiv:astro-ph/0202194. Bibcode:2002MNRAS.331L..41B. doi:10.1046/j.1365-8711.2002.05417.x. S2CID 18383063.
  23. ^ Siess, Lionel (2000). "Computation of Isochrones". Institut d'Astronomie et d'Astrophysique, Université libre de Bruxelles. Archived from the original on 2011-05-05. Retrieved 2007-03-24.
  24. ^ Jao, Wei-Chun; Henry, Todd J.; Subasavage, John P.; Brown, Misty A.; Ianna, Philip A.; Bartlett, Jennifer L.; Costa, Edgardo; Méndez, René A. (2005). "The Solar Neighborhood. XIII. Parallax Results from the CTIOPI 0.9 Meter Program: Stars with mu >= 1.0" yr-1 (MOTION Sample)". The Astronomical Journal. 129 (4): 1954–1967. arXiv:astro-ph/0502167. Bibcode:2005AJ....129.1954J. doi:10.1086/428489. S2CID 16164903.
  25. ^ Kervella, Pierre; Arenou, Frédéric; Thévenin, Frédéric (2022-01-01). "Stellar and substellar companions from Gaia EDR3. Proper-motion anomaly and resolved common proper-motion pairs". Astronomy and Astrophysics. 657: A7. arXiv:2109.10912. doi:10.1051/0004-6361/202142146. ISSN 0004-6361.
  26. ^ Kervella, Pierre; Arenou, Frédéric; Mignard, François; Thévenin, Frédéric (2019-03-01). "Stellar and substellar companions of nearby stars from Gaia DR2. Binarity from proper motion anomaly". Astronomy and Astrophysics. 623: A72. arXiv:1811.08902. doi:10.1051/0004-6361/201834371. ISSN 0004-6361.

External links

Known celestial objects within 20 light-years
Constellation of Musca
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